Gearbox oil change

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PMB
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Joined: 04 Apr 2022, 11:07

Gearbox oil change

Post by PMB »

Hello all, just joined this forum.
I am looking for some advice changing my 2014 c5 tourer 2.0 hdi gearbox oil.
What tool do I need to use to remove the plug and how many litres of oil is recommended?
Many thanks in advance.
PMB
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Joined: 04 Apr 2022, 11:07

Re: Gearbox oil change

Post by PMB »

One point to note, I have a manual gearbox. Do I still need a level diagnostic tool after changing the oil?
What quantity do I need and what tool do I need to remove the plug?
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GiveMeABreak
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Re: Gearbox oil change

Post by GiveMeABreak »

Ok, scrap that, I mistakenly assumed you meant you had an Auto gearbox, so I've deleted my previous post as it is irrelevant to a manual box.

No you don't need a diagnostic tool to change the manual gearbox oil. You will need to replace the drain cap with a new seal though.

The oil quantity after draining can be different on the 6 speed ML6 box depending on the version. The ML6C box can be made with or without fins and this affects the capacity:

ML6C Gearbox
Gearbox casing with fins 1.9 litres
Gearbox casing without fins 2.6 litres
gravity oil feed.JPG
It has to be gravity filled using the vent hole at 'a' as these are 'filled for life', so there is no general filler port.

ESSO 75W80 EZL 848 or TOTAL 75W80 H6965
PMB
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Joined: 04 Apr 2022, 11:07

Re: Gearbox oil change

Post by PMB »

Marc, many thanks for your help. Is the drain plug tool an 8mm bar type?
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GiveMeABreak
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Re: Gearbox oil change

Post by GiveMeABreak »

The plug is listed as DIAM 16X22-2 with a tightening torque of 3 daNm.
PMB
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Re: Gearbox oil change

Post by PMB »

Many thanks for your help
Steve Walsh
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Re: Gearbox oil change

Post by Steve Walsh »

Mine has a 8mm square hole, I had to make a special one to fit as it was just above subframe with no room.
PMB
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Re: Gearbox oil change

Post by PMB »

Having spent time under the car today, I am unable to find the gearbox drain plug. Help please?
Steve Walsh
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Re: Gearbox oil change

Post by Steve Walsh »

Above subframe on lower part of gearbox, Not easy to get at, I made a tool and also used a piece of plastic to guide oil into a container
PMB
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Re: Gearbox oil change

Post by PMB »

Steve would you please photo the tool you have made so I can replicate.
Steve Walsh
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Re: Gearbox oil change

Post by Steve Walsh »

First thing in morn
PMB
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Re: Gearbox oil change

Post by PMB »

Thank you
Steve Walsh
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Re: Gearbox oil change

Post by Steve Walsh »

1.jpg
1.jpg (7.17 KiB) Viewed 81 times
Not my best attempt at a tool but was in the middle of servicing my C5 and did it in a rush.

It is a square bar, 8mm filed from a round one as it was all I had, welded into a 10mm nut 17mm spanner size and I can't remember why I added the washer.

I also used a piece of plastic cut from a 5 litre oil container to direct the oil from the drain above the chassis into a drain tub.

If you are still struggling with it let me know and I could remove my undersheild and take some photo's

Steve
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Re: Gearbox oil change

Post by PMB »

Steve, I do appreciate your help with this, I am still struggling to locate the drain plug.
If it is where you say it is i.e. above the subframe, how do youn attach your socket to your made up tool and get leverage when the subframe is in the way.
I was under the car again last night unable to work this out. Help please.
Steve Walsh
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Re: Gearbox oil change

Post by Steve Walsh »

I used a spanner on the nut